Anticipation timing device



R. V. HILDEBRANT E TAL ANTICIPATION TIMING DEVICE April 24, 1962 3,031,543

Filed Oct. 19, 1960 2 Sheets-Sheet 1 PREDETERMINED START fPLANES PATH f OF TIMING CYCLE POINT OF RELEASE A WITH NO ANTICIPATION POINT OF RELEASE FOR HIT ON TARGET ANTICIPATED RELE SIGNAL T0 OCCgRr FOR RELEASE POINT- B ASE HERE

BOMB PATH WITH NO 4 ANTICIPATION 3 BOMB PATH FOR HIT g :3, 5 5 l I 3 GROUND TARGET\ ON TARGET PREDETERMINED 2 OFF TARGET J DISTANCE 1 INITIAL POINT To TARGET II I INVENTORS RICHARD v. HILDEBRANT ROBERT c. w LLS BY A T TOR NEY l 1962 R. v. HILDEBRANT ETAL 3,031,543

ANTICIPATION TIMING DEVICE Filed Oct. 19, 1960 2 Sheets-Sheet 2 b l TIMER In,

DRIVE '3 lo MECH. zp/ NOT BO RELEASE BOMB INVENTORS RICHARD V. HILDEBRANT ROBERT C. WE LS,

States Patent nice 3,031,543 7 ANTICIPATION TIMING DEVICE Richard V. Hiidebrant, Vestal, and Robert C. Wells, Scotia, N.Y., assignors to the United States of America as represented by the Secretary of the Air Force Filed Oct. 19, 1960, Ser. No. 63,704 Ciaixns. (Cl. 20034) This invention relates to anticipating devices for anticipating the time lapse between the reception of a power signal for actuating a mechanism and actual actuation of the mechanism. More particularly, the invention relates primarily to bomb release mechanisms for high speed aircrafts, missiles,-etc., wherein a time control mechanism is set for actuating a bomb release device for release of a bomb or explosive device at the end of a predetermined time lapse.

In high speed aircraft employing high explosive bomb devices, such as disclosed in US. Patent to J. A. Ryan, No. 2,898,809 patented August 11, 1959 wherein an intervelometer or timing mechanism is provided which is set for a predetermined time interval and initiated into operation during flight at a predetermined distance from a selected target for actuating a release mechanism for dropping a tossing a bomb or explosive device toward the target at the termination of the set cycle of the intevelometer it has been found that a time delay or lag occurs due, among other things, to the time required to actuate the bomb release mechanism after the power signal from the intervelometer or other time control device is received by the bomb release device for initiation thereof. This time delay effects the release point in the flight to a considerableextent. As a result there is a variation in the disposition of the bomb device over or on the target from its planned trajectory. The subject invention proposes to compensate for or anticipate this variation in time and provide means for making a correction automatically for this time delay so that the actual release of the explosive device for dropping or toss bombing occurs at the actual termination of the predetermined clasped time period and not subsequent thereto.

Variations in the speed of high speed aircraft, while not necessarily changing this time delay period between the bomb dropping mechanism release signal and the actual release of the bomb does,however, eifect the release point with respect to'the target. For instance, the aircraft will travel further between the termination of the initially. set

time period for release of the explosive deviceand the actual release of theexplosive device when its speed is greater than when its speed is slower. My improved anticipating device compensates for this variation also.

Other object and advantages of the invention will be apparent from the following description and accompanying drawings in which like parts are referred to by like reference characters.

FIG. 1 is a schematic or diagrammatic view illustrating in dotted lines the point of release and trajectory of a bomb deviceat the .end of a predetermined time period in a toss bombing operation without the employment of my anticipating device, and showing in full lines withthe same timing cycle and initiation thereof thechange in location of the trajectory resulting from the application of my improved automatic anticipation device;

FIG. 2 is a simple diagrammatic view further illustrating the timing device with the anticipating mechanism applied thereto; and

FIG. 3 is a schematic diagram illustrating the timing cycle of the intervelometer or timing device for effecting the release device.

In many types of equipment, such as servomechanisms,

release mechanisms, missiles, planes, etc., a delay or re .response, and, as intimated above, in many cases, this time delay results in an error in the programming of the operations of the device or missile, or a delay in the release of bombs, etc. To eliminate the error caused by this delay time the anticipating device of the subject invention is inserted to advance the time of the initiation signal so that the event will occur at the proper planned instant.

Illustrating one application of my anticipating device, reference being made to FIG. 1, which is in the fire control system of a fighter plane for bombing a target indicated at 1 located at a known distance 2 from an initial or reference point 3, and flying at a speed 4 and altitude 5, the plane must pull away from the target area prior to the impact. FIG. 1 illustrates schematically the flight pattern. The plane is initially flying straight and level and starts its planned pull up at some point 6 which is determined by a predetermining cycle of a computer timing device. At some point in time B the computer or timer indicates a solution time and the bomb release relay is closed. Normally, because of the delay time in the actuation of the bomb release mechanism between the release signal and the actual release, the actual release point occurs at some subsequent point in the pull-up cycle, indicated at C. This causes a deviation of the desired trajectory of the bomb, indicated by the dotted line 7 from the planned trajectory indicated at 8. As a result the bomb would miss the target 1. However, by providing the proper anticipation time by employing my anticipating device shown in FIG. 2., the bomb release signal will be advanced in time to the point A in the pull-up and the bomb will be ejected from the plane at the point B and will follow the prescribed trajectory 8 and the desired hit on the target will result.

To illustrate simply, reference is made to FIG. 2, in which my anticipating device is schematically shown, the reference numeral 9 represents a support in the plane for the mechanism 10, comprising a gear or timer disc 6 which is driven by a shaft 11 from an adjustable computer device 12 with adjusting means 13 for driving the disc uniformly at different or variable rates of rotation 19.

The disc or gear G is provided with a gear portion 14 which meshes with a smaller disc G having a gear portion 16, the smaller disc or gear G being journalled on a vertical support or standard'17 carries a crank pin 18 to which a connecting rod 19 is. pivoted at one end, the other end being connected to a piston 20 operating in a dash pot cylinder 21 which is fixed to one end of lever arm '22 fulcrumed intermediate its ends at 23 on a vertical support or standard 24 located at a distance a from the axis of the small gear G The other end or arm 25 extends past the side of the timing gear G a distance b and has on the end thereof a circuit closing device 26 such as a microswitch having a contact button at N located in the path of a fixed contact projection at M at or near the periphery of the gear G The microswitch through suitable conventional circuits 29,-relays 30, etc., operates the bomb release device 31 for releasing the bomb when the contact at M closes the microswitch at N.

The arm 25 is connected at some point 32 by a calibrated spring 33 to the support 9 at 34 exerting predetermined downward pressure on the arm 25 'as determined by the distance c from the lever fulcrum 23.

A vertical rest or stop arm 35 is provided limiting the downward movement or restposition of the arm 25.

To illustrate What is required in the operation, reference is made particularly to FIG. 3. The bombing computer shaft 11 has a rotation output 0 which turns at a variable rate 6. When the contacts M and N are closed there is a release signal to which is insertedan anticipation time T by reason of the contact N being advanced inthe direction of the arrow by a value 0 =0T.

'In the advance of contact N as seen in FIG; 2 the gear minim-:ke. arm=kc. $6 6T Then nr da kc. 1)

Therefore, the system produces an anticipation time T, which is independent of the closing rate 0. The arm a dash pot 21 and spring 33 constitute a second order system which must have proper response for the system. For this application, the useful motion of 0 is small and the system can be mechanized in this manner Without appreciable error.

The use of the dash-pot provides a large amount of damping which is required to overcome friction, also temperature effects are less than other damping means, and changes in damping with altitude are small.

This anticipating device can also be used in missile programming to eliminate errors due to response time of missile and control surface. If the missile has a pitch rate 0 which must be zero when the missile has reached an angle 0, the delay time will result in an error in 0 unless an anticipation system such as proposed is used.

In the operation, when the disc G is released for starting the timing cycle at the proper adjusted rate the contact M moves slowly toward its contacting position for contact with the release contact N where the actual power or release action should occur. As the disc rotates toward this position the anticipating device comes into operation. The gear G rotates the gear G in the direction N9 drawing the piston 20 downward. This action on the dash-pot cylinder 21 rocks the contact advancing lever 25 counterclockwise against the tension of the calibrated spring 33. The expansion of the space in the area above the piston in the dash-pot drawing the cyl inder 21 downwardly and the contact or microswitch 26 is advanced toward the switch advancing contact M at a predetermined rate depending upon the relative lengths of the lever arms a and b, and c, and the strength of the spring 33, and the expansion of the dash-pot inclosed area.

This action is calibrated to equal the delay time between the programmed contact closing or bomb release instant and the end of the delay time occurring thereafter due to the subsequent actual operation of the apparatus or bomb release mechanism.

When the gear G moves faster, for instance, when the speed of an aircraft is greater, the piston is correspondingly moved downward at a faster rate and this rocks the lever 25 farther so as to advance the microswitch contact M causing the bomb release contact (microswitch) 26 to be engaged by the contact M earlier, thereby advancing the release contact N toward the contact M just sufficient to equal the movement of the disc G through the period of time equal to the time delay between the release signal and the actual release actuation in response to the signal. The device advances the release signal in a predetermined ratio to the rate of rotation of the gear G The drawings are schematic and therefore are for exemplary purposes in explaining the invention rather than in a limited sense and changes may be made in the construction without departing from the spirit and scope of the invention as defined by the accompanying claims.

We claim:

1. In a time delay anticipating device of the class described, a support, a time delay compensating lever means pivotally mounted on said support, energizing switch means fixed to one end of said lever for producing an energizing signal, means responsive to said energizing signal having a predetermined time delay, rotary contact means for closing said switch means rotatable at a predetermined rate in one direction, means for rocking said lever means to move said switch means in a direction in opposition to the direction of rotation of said rotary member to advance the position of said energizing switch means a predetermined degree relative to the position of the rotary contact means during rotation thereof, spring means yieldably urging said lever in the direction of rotation of said rotary member, stop means on said support for limiting movement of the lever in the last mentioned direction, and dash-pot connecting means connected between the rotary member and said lever for yieldably moving said lever away from said stop means in opposition to said spring means for moving said lever to advance said energizing means toward said contact means to a predetermined degree to compensate for said time delay.

2. In a time delay anticipating device of the class described, a support, a lever arm rockably carried by said support, energizing means carried by said lever arm for producing an energizing signal, means responsive to said energizing signal having a predetermined time delay, a rotary contact member rotatable at a predetermined rate having contact means thereon for engagement with said energizing means during rotation thereof for energizing the same to produce said energizing signal, means for advancing said energizing means in opposition to the rotation of said rotary member for advancing the time of engagement of the energizing means with the rotary member to compensate for said predetermined time delay, comprising a second rotary member driven by said first rotary member, having a crank thereon, and a dash-pot connection between said crank and said lever arm for rocking said lever arm during rotation of said first rotary member for advancing said energizing means a predetermined degree relative to the rate of rotation of said first rotary member in opposition to the direction of rotation of the first rotary member to compensate for said time delay.

3. In a time delay anticipating device a support, a timer disc, timer means for rotating said timer disc in one direction at a predetermined rate, contact means fixed on said disc for rotation therewith, a contact lever pivoted to said support intermediate its ends, contact means fixed to one end of said lever for contacting relation with said first mentioned contact means for closing an energizing circuit, calibrated spring means between said lever and said support for yieldably resisting rocking movement of said lever and contact means thereon in a direction in opposition to the direction of movement of said disc in said one direction, a second (smaller) disc connected to said timer disc for positive rotation therewith in opposite direction to the direction of rotation of the timer disc and yieldable connecting means between the other end of said contact lever and said smaller disc eccentric thereof for yieldably rocking the contact mounted end of said lever toward said contact means on said timer disc at a rate proportional to the rate of rotation of said timer disc for advancing the contact engagement in predetermined ratio to the ratio of rotation of the timer disc.

4. Apparatus as claimed in claim 3 in which said yieldable connecting means between said lever and said smaller disc eccentric thereof comprises a piston and dash-pot cylinder construction.

5. Apparatus as set forth in claim 4 in which the dashpot cylinder is fixed on the end of the lever and contains a piston connected to said smaller disc eccentric thereof by a crank and connecting rod, and the dash-pot contains a yieldable fluid medium.

References Cited in the file of this patent UNITED STATES PATENTS 2,578,632 Miller Dec. 11, 1951 

